Dental treatment centers have generally relied upon a controlled source of compressed air to drive air motor or turbine powered handpieces to effect treatment. Control of the speed of the handpiece is related to the pressure of the air reaching the air motor or turbine, and the air pressure is controlled by a pedal or similar device. Manipulation of the pedal allowed the practitioner to control very precisely the turbine speed and therefore the speed of rotation or oscillation of the tool mounted in the handpiece.
More recently, electric drive handpieces including compact electric motors that provide driving torque to the tool have found favor owing to their flexibility in controlling both the speed of operation as well as the torque exerted by the tool. However, most existing dental treatment center installations are configured for pneumatic handpieces and pneumatic control thereof. Generally speaking, replacement of the entire treatment center to support electric drive handpieces is cost prohibitive.
With the introduction of the ELECTROtorque TLC and the ELECTROtorque Plus systems, the assignee of the instant application offered a system providing pneumatic control of an electric drive for a handpiece. These devices tailored to the older dental treatment facility having only compressed air available as a drive medium, opened up the possibility of expanding the types of drive instruments that could be used with a treatment center. These devices operated by converting the compressed air previously used to drive the air motor or turbine into an electric control signal for driving an electric motor for operating the handpiece.
A device, such as the ELECTROtorque TLC or ELECTROtorque Plus, that converts the compressed air into a control signal must operate with a variety of treatment centers and with a variety of air supply conditions and pressures. To account for variations in air supply conditions, these systems and those like them require a calibration process to associate a maximum electric motor speed with a maximum system pressure of the treatment unit. The calibration process must be performed frequently and requires a number of specific and carefully planned steps taking time and effort.
Not only providing an electric control signal to the handpiece, the device converting the system air pressure to an electric control signal also provides cooling air to the handpiece and air and water media used in the treatment process. The system also needs to be flexible in accepting multiple different handpieces used in various procedures. Changing from one handpiece to another must be quick and easy and cannot require complicated changing over of medium line connections or complicated coupling of the electric motor to the handpiece. Generally, the initial setup, configuration, reconfiguration and use of the system should be simple and not require special training or procedures.